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What are the problems with map projections?
Because you can’t display 3D surfaces perfectly in two dimensions, distortions always occur. For example, map projections distort distance, direction, scale, and area. Every projection has strengths and weaknesses. All in all, it is up to the cartographer to determine what projection is most favorable for its purpose.
Why is there no perfect map projection?
Because the sphere is not a developable surface, it is impossible to construct a map projection that is both equal-area and conformal.
What should I consider when choosing a projection?
When you choose a projection, the first thing to consider is the purpose of your map. For general reference and atlas maps, you usually want to balance shape and area distortion. If your map has a specific purpose, you may need to preserve a certain spatial property—most commonly shape or area—to achieve that purpose.
Are there projection maps that preserve all areas?
While we have map projections that can preserve areas or form everywhere on the map, there isn’t one that can preserve distances everywhere. There are only projections that let you preserve distances relative to just one or two points on the map.
Can a projection preserve distance between two points?
There are only projections that let you preserve distances relative to just one or two points on the map. Distances to and from the center of an Azimuthal Equidistant map are shown correctly, but distances between any other two points are distorted. When a projection preserves distance, we call it equidistant.
Why do we need to distort the Earth to make a map?
Likewise with the Earth—if we want to make a map, we need to distort the Earth’s surface to flatten it. The good news is that map projections allow us to distort systematically; we know exactly how things are being stretched or squashed at any given point.